v3.26.1
Long-term investments (Details)
Jun. 30, 2026
USD ($)
Jun. 30, 2026
CNY (¥)
Dec. 31, 2025
CNY (¥)
Financial Instruments Owned and Pledged as Collateral [Line Items]      
Cost method investments $ 176,188 ¥ 1,200,000 ¥ 1,200,000
Less: Impairment loss 161,959 1,103,089 1,103,089
Total 14,229 96,911 96,911
Investment 1 [Member]      
Financial Instruments Owned and Pledged as Collateral [Line Items]      
Cost method investments 88,094 600,000 600,000
Investment 2 [Member]      
Financial Instruments Owned and Pledged as Collateral [Line Items]      
Cost method investments $ 88,094 ¥ 600,000 ¥ 600,000